EXCLUSIVE cable network Plum TV has fired more than 20 people and is on the brink of collapse, said a source. “They will probably have to start selling stations soon,” said the insider. Plum – created by Tom Scott, the marketing genius behind Nantucket Nectars – reaches luxury resort towns like Aspen, the Hamptons, Martha’s Vineyard, Miami Beach and Nantucket. A Plum TV rep said the company was doing fine: “We did undergo a reorganization last week. We did not lay off 26 employees. We simply streamlined our operation, eliminating 11 jobs where people were doing duplicate work . . . We are not closing any stations.”